The invention is generally in the field of laser-induced breakdown spectroscopy (LIBS) and more particularly an apparatus and system designed for laser-induced breakdown spectroscopy measurements.
For various applications, methods are needed for determining the material constitution of a sample. One of the known methods is laser-induced breakdown spectroscopy (LIBS), which involves focusing a laser beam onto a surface of a sample with a high enough power density to transform a small part of the sample material into a state of plasma. Optical emissions from the plasma plume are collected with light collection configuration, and the spectral distribution (i.e. intensity as a function of wavelength) of the collected optical emissions is analyzed in a spectrometer that produces information in electronic form describing the spectral distribution. Since atomic and molecular constituents of sample materials have characteristic optical emission spectra, the information produced by the spectrometer reveals the constituents of that part of the sample onto which the laser beam was focused or directed.
The sample may in principle be solid, liquid or gaseous. In the case of a gaseous sample the concept of a “surface” of the sample does not exist, but the laser beam is just focused into the gaseous sample. A drawback of the known LIBS measurement devices is its certain bulky structure and limited applicability to field use. Traditionally LIBS has been considered to be applicable under laboratory conditions only. Efforts have been made to reduce the form factor of LIBS devices, as evidenced by U.S. Pat. No. 7,394,537 to Lindfors et al and U.S. Pat. No. 7,821,634 to Dillon et al. However, these devices still create safety issues for the users and the laser components are still subject to damage when in portable form due to the requisite size for energy consumption and stabilization of the output wavelength, among other limitations including heat consumption, complex optics for light collection and lack of a robust design for continuous alloy analysis.